Thus finally we must abandon even the title. It is not the proletariat that is being formed into a class: it is a variety of persons some of whom are separated from the system of production. Processes of forming workers into a class do not take place in a vacuum; rather, they are inextricably tied to the totality of processes through which collectivities appear in struggle at particular moments of history. And the outcomes of these processes, while not arbitrary, are not determined uniquely by the structure of social relations. More than one outcome lies within the limits set by those relations.

"Proletariat into a Class: The Process of Class Formation from Karl Kautsky’s The Class Struggle to Recent Controversies", Politics & Society (1977)

Marx may have erred in analyzing the nature of this conflict. Interests of workers and capitalists may not be irreconcilable under all circumstances, and workers may see the choice between capitalism and socialism differently depending upon the specific political and economic conditions under which they live.

Adam Przeworski and Michael Wallerstein, The American Political Science Review (Jun., 1982)

Social democrats will not lead European societies into socialism. Even if workers would prefer to live under socialism, the process of transition must lead to a crisis before socialism could be organized.

Capitalism and social democracy (1985), Ch 1. Social Democracy as a Historical Phenomenon

Capitalism is a system in which many scarce resources are owned privately, and decisions about allocating them are a private prerogative. Democracy is a system through which people as citizens may express preferences about allocating resources that they do not privately own. Hence the perennial question of political theory and of practical politics concerns the competence of these two systems with regard to each other. Is it possible for governments to control a capitalist economy? In particular, is it possible to steer the economy against the interests and preferences of those who control productive wealth?

Adam Przeworski and Michael Wallerstein, The American Political Science Review (Mar., 1988)

Democracy can be an equilibrium: a system of "self-government" in which the distinction between the rulers and the ruled disappears.

Adam Przeworski (1991) Democracy and the Market: Political and Economic Reforms in Eastern Europe, p. 26

If a Martian were asked to pick the most efficient and humane economic systems on earth, it would certainly not choose the countries which rely most on markets. The United States is a stagnant economy in which real wages have been constant for more than a decade and the real income of the bottom 40 percent of the population declined. It is an inhumane society in which 11.5 percent of the population, some 32 million people, including 20 percent of all children, live in absolute poverty. It is the oldest democracy on earth but also one with the lowest voting rates among democracies and the highest per capita prison population in the world. The fastest developing countries in the world today are among those where the state pursues active industrial and trade policies; the few countries in the world in which almost no one is poor today are those in which the state has been engaged in massive social welfare and labor market policies.

In: Journal of Democracy. Vol. 3, Nr. 3 (1992), p. 46

The simple answer to the question with which we began is that we do not know whether democracy fosters or hinders economic growth.

What makes democracies sustainable, given the context of exogenous conditions, are their institutions and performance. Democracy is sustainable when its institutional framework promotes normatively desirable and politically desired objectives, such as freedom from arbitrary violence, material security, equality, or justice, and when, in turn, these institutions are adept at handling crises that arise when such objectives are not being fulfilled.

Adam Przeworski, Sustainable Democracy (1995), Conclusion

Since in this view dictatorships generate development while development leads to democracy, the best way to democracy was said to be a circuitous one. Yet common sense would indicate that in order to strengthen democracy we should strengthen democracy, not support dictatorships. And, even if G. B. Shaw warned that "common sense is that which tells us that the world is flat," the lesson of our analysis is that this time it is the best guide. With development, democracy can flourish in poor countries.

The conclusions are self-evident, so I just state them. Electoral winners and losers obey the results of democratic competition and thus democracy is sustained merely as a consequence of political forces pursuing their interests. Whether this explanation is sufficient or some cultural patterns are necessary for democracy to endure is just hard to tell, as is whether democracy can survive even when it is not supported by economic self-interest.

Chapter 5. "Why Do Political Parties Obey Results of Elections?" in Democracy and the Rule of Law (2003) edited by José María Maravall and Adam Przeworski

The central thing I learned was that reformism was a rational strategy for workers. It was in the interest of workers to support capitalist democracy. An electoral victory of pure workers’ parties was not historically feasible, because the assumption that manual workers in industry and transportation would one day become the overwhelming majority of the population in industrializing countries was mistaken.

interview by Gerardo Munck on February 24, 2003, published in Passion, Craft, and Method in Comparative Politics edited by Gerardo L. Munck and Richard Snyder

In general dictators have not done better at [economic] policies than democrats—far from it. Most dictators have ravaged their countries for personal gain. Scholars have asked whether democracy helps or hurts the economic growth of poor countries and despite many surveys, have come to no conclusive answer.

In: Fareed Zakaria (2007) The Future of Freedom. p. 251

Is “democracy,” as we understand the term today, an implementation of “self-government,” as this ideal was formulated when representative institutions were first established? The evidence is mixed.

Democracy and the Limits of Self-Government (2010), Chapter 8. Democracy as an Implementation of Self-Government in Our Times

There are other types of circumstance in which capacity to predict will support one descriptive cut at a problem over others. For instance, Przeworski et al. have shown that although level of economic development does not predict the installation of democracy, there is a strong relationship between level of per capita income and the survival of democratic regimes.

Ian Shapiro, The Flight from Reality in the Human Sciences (2005), Chapter 5. Problems, Methods, and Theories in the Study of Politics: Or, What’s Wrong With Political Science and What to Do about It